Re: Need guidance with first build!
Not quite sure what you mean by "default gap". Are you refering to the cylindrical slide in the carburetor? That is the throttle barrel which is lifted by the throttle cable. The heigth determins the idle speed which is adjusted by the small screw, the one with the spring on it. You'll need to have the engine running before you can adjust that speed, therefore the 'gap' I think you're looking at. Seal the carb to the intake manifold with a good silicone gasket sealer, filling the gaps on the carb tabs.
As for break in, just don't abuse your engine for the first few miles or the first couple of tanks of fuel. I use Opti-2 oil at 100:1 mix but that is frowned on by many who believe that a good quality two stroke oil mixed 24:1 is a good break in mix. After a couple of gallons you can reduce the oil to a 32:1 mix and you should be good. Have fun, ride safe and let us know if you need further help.
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